How To: 20-cwt GS trailer hand brake

[Grant Bowker]

Step 1 was to buy a brake handle. $9.99 plus postage, the seller had described it as a Fird (easy to see the typo they made... but limits the searchability for the auction) part so I was the only bidder. Once I had the lever I enlarged the manual drawing from the original 2" size to match the length of the handle. All aspects of the handle fit so it seemed like a good start. Then the dimensions of the mounting pattern and cable location were checked against the trailer mounting points, they matched too so it seemed the plan was good.

Images are the eBay handle before and after removing from the original mounting bracket. The pivot rivet had enough length remaining that it could later be peened to make a new head.

[Grant Bowker]

New parts were made to the size given by the "enlarged to full size" diagram from the parts list. The main upright was 3/16" to match the ratchet plate on the eBay handle, stiffening webs 1/4" to match the diagram, base plate 3/8" to match the diagram, sloped plate for cable/rod to pass through and its curved wedge support a mix of 1/8' and 3/16" from the offcuts bin. All parts were welded together and the raised profile of a mig weld ground to resemble the dish profile of the original casting or forging. At this point I still hadn't seen an origina, I was working from a mix of known dimensions, period drawing (wildly enlarged but seemingly dimensionally sound) and thinking about it in terms of "how many ways could the part be made" to fit what I knew.

Images are the welded assembly before and after sandblasting and phosphate treatment. The sandblasting left a quite uniform surface that encouraged me to carry on.

[Grant Bowker]

Not much more to the assembly. After sandblasting the rivet that acts as the handle pivot was peened over and the assembly painted. At this stage I was quite satisfied with the result, it looked like a single piece and appeared dimensionally and functionally correct.

[Grant Bowker]

When we went up to the Dan Caldwell's to pick up the HUP parts for Rob Clarke I took the chance to look inside the FAT bodies they have in the back yard and there was a parking brake handle of the type I'd made staring me in the face. (Aside - I think Christie would like him to sell the FAT bodies if a suitable buyer can be found).
Compared to the fabricated part, the main upright is a bit thicker, all facets of the base have more casting draght than I had expected but unless you know what to look for, I think my fabrication is an acceptable facsimile until an original part jumps out of the bush.
Images are the original parking brake lever assembly.